The projectile’s mass is not needed.

Question

 The projectile must be launched on the horizontal plane.
 The earth drops 8 inches for every mile traveled.
 The acceleration due to gravity is 9.81 meters per second squared.
 Ignore air resistance.
You will have to calculate how far an object drops every second due to gravity

How fast does an object need to travel to stay in orbit for three seconds?

Please help me. I'm horrible at physics.

Answer 1

falling things drop at the rate of 1/2 g time^2=16t^2
if it falls 2/3 ft each mile, then the time to go a mile is
2/3 ft=16t^2
or t= sqrt(2/48)
so how far does it drop in one second?
d=2/3 *1sec/sqrt(2/48)=3.26ft
on the last part, it seems to me that it matters what the initial altitude is...

Answer 2

Ok thank you so much, but How fast does an object need to travel to stay in orbit for three seconds? Also thanks for explaining it to me.